TMDM-7621: "Change impact analysis results to user friendly messages"

Changes common module to a better maven compliant structure (separate resources and sources).
Adds i18n package for data model analysis.
(https://jira.talendforge.org/browse/TMDM-7621)
TMDM-7615: "Sub-type should not allow to define field with the same name with it's supertype"

Adds new validation rule to check for override of fields in sub types (sub type is not allowed to declare an element with same name as an inherited one).
Ensures validation rule is performed for all fields.
Adds unit test for issue.
(https://jira.talendforge.org/browse/TMDM-7615)
Misc: Don't perform validation tasks on system model (no need for validation).
TMDM-7615: "Sub-type should not allow to define field with the same name with it's supertype"

Fixes issue relative to FK field: getDeclaringType() was returning containing type iso. declaring's.
(https://jira.talendforge.org/browse/TMDM-7615)
Merge remote-tracking branch 'origin/maintenance/5.6' into prototype/metadata_builder

Conflicts:
	main/plugins/org.talend.mdm.commmon/src/main/java/org/talend/mdm/commmon/metadata/compare/Change.java